By Caroline Cheese
BBC Sport at Wimbledon
Federer is yet to drop a set at this year's Championships
Defending champion Roger Federer made short work of Mario Ancic as he booked his place in the Wimbledon semi-finals with a crushing 6-1 7-5 6-4 victory.
Federer emerged from a rain delay in sizzling form, wrapping up the opening set in just 20 minutes.
Ancic, who had played 14 sets in his previous three matches, put up a better fight in the second set but dropped serve crucially at 5-5.
And one more break in the third was enough for Federer to seal the win.
The top seed - still yet to drop a set in the tournament - will face Marat Safin or Feliciano Lopez in Friday's semi-final, and neither will hold much fear after a supreme display against Ancic.
"I'm playing great, serving excellent," said Federer, who landed 76% of his first serves and did not face a single break point.
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"It was a tough day with the rain delays and it broke my momentum a little bit because I started well.
"It's a long way to get to the semis. But I know how to win two more. I've done it before so I'm looking forward to the challenge."
Ancic, famously, was the last man to beat Federer at Wimbledon.
However, that was back in 2002 before Federer's period of dominance at Wimbledon - and in the men's game - began.
Since then, Federer has beaten Ancic five times in a row, racked up five straight Wimbledon titles and won 63 - now 64 - successive matches on grass.
So Ancic's chances of repeating that famous win were already slim and were not helped by a leg injury and an energy-sapping five-set match against Fernando Verdasco in the previous round.
The Croat looked sluggish from the off, while Federer was at his magnificent best, allowing his opponent just 10 points in a one-sided first set.
Ancic appeared refreshed after another rain delay but his second double fault came just at the wrong time, allowing Federer to break for a 6-5 lead.
Federer served out to 15 and had chances to break again in a dazzling opening game of the third set.
But after 16 thrilling minutes - only four minutes less than the entire first set - Ancic held.
But it was to prove only a brief reprieve. Federer broke for a 3-2 lead and comfortably served out victory after one hour and 41 minutes.
Ancic had no complaints afterwards and instead preferred to look back on his run in the tournament.
"I'm so proud of myself and how I was doing that second and third set, going really aggressive, pushing myself to play like that," he said.
"He makes you play the hardest you can, and you can't give him anything.
"I will take a lot of positive things from here and keep on going. I mean, I know where I want to be and I know that I still want to continue."